On 10/26/2017 03:46 AM, Alexey Kardashevskiy wrote: > A "powernv" machine type defines an ISA bus but it does not add any > DMA > controller to it so it is possible to hit assert(fdctrl->dma) by > adding "-machine powernv -device isa-fdc".
The same happens with the Alpha machine. On 12/13/2017 03:19 AM, Hervé Poussineau wrote: > Le 08/12/2017 à 22:29, John Snow a écrit : > [...] >> >> It looks like Herve was working on decoupling floppies from i8257, but >> perhaps didn't get all the way through -- I'm not actually clear on what >> work remains to be done here, maybe he can chime in if he's still >> interested in the project? >> > > Indeed, I worked on decoupling floppies (and other ISA devices) from > i8257, for three reasons: > 1) having a working floppy on MIPS Magnum machine. fdc is PC-compatible, > but DMA controller is not i8257-compatible. > 2) reimplement another ISA bus with a somewhat i8257-compatible DMA > 3) for fun, support multiple ISA buses on a same machine but on > different PCI bridges. > > I failed on point 1), mostly due to lack of documentation. > I succeeded on point 2), by having locally some patches for a ISAPNP > bus, where IO/IRQ/DMA addresses of ISA devices can change dynamically, > and devices can be discovered by operating system. > About point 3, most of the patches are ready, but some details are still > to be fixed. I'm having hard time refactoring all these PC chipsets, I'll make some room to send my current work as RFC before soft freeze. Regards, Phil.
